


Calculated Risks

by mutuallyexclusive



Category: Haikyuu!!
Genre: Alpha/Beta/Omega Dynamics, Childhood Friends, Eventual Romance, Eventual Smut, F/M, Family Drama, Fluff, Friends to Lovers, Implied Sexual Content, Jealousy, M/M, Multi, Non-Traditional Alpha/Beta/Omega Dynamics, Other Additional Tags to Be Added, POV Second Person, Pining, Roommates, Sibling Incest, Slow Burn, Threesome - F/M/M, Twincest, past bullying
Language: English
Status: In-Progress
Published: 2021-01-29
Updated: 2021-02-03
Packaged: 2021-03-15 08:00:39
Rating: Mature
Warnings: Creator Chose Not To Use Archive Warnings
Chapters: 2
Words: 3,076
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/29060952
Author URL: https://archiveofourown.org/users/mutuallyexclusive/pseuds/mutuallyexclusive
Summary: When a sudden fire at your dormitory building leaves you stranded in Osaka in the middle of the semester, you have no choice but to turn to a family friend for help. And if said family friend happens to be a pair of twins who were also your childhood bullies... Well, beggars can’t be choosers, right?
Relationships: Miya Atsumu & Miya Osamu, Miya Atsumu & Miya Osamu & Reader, Miya Atsumu & Reader, Miya Atsumu/Miya Osamu, Miya Atsumu/Miya Osamu/Reader, Miya Atsumu/Reader, Miya Osamu & Reader, Miya Osamu/Reader
Comments: 14
Kudos: 123





	1. Chapter 1

**Author's Note:**

> Let me preface this by saying that while I do not condone any incestuous relationships in real life, I also do not actively hate on them. This is merely a work of fiction that provides me a platform to tackle/write about problematic issues and improve my own writing, in addition to combining my guilty pleasure of Atsumu/Osamu with Reader fics.
> 
> If you're okay with everything in the tags, then please go ahead and enjoy the story!

“And this is where you’ll be staying,” Osamu says as he pushes the door open.

You roll your suitcase to a stop before peering into the room curiously. The room is lightly furnished, containing a single bed pushed up against the wall, a nightstand, and a wardrobe in the corner. Directly in front of you is a wide window with thick blue curtains pulled to the sides, allowing ample sunlight to filter into the area. On the other side of the room are a foldable table and a plastic chair you suspect to be last-minute additions.

The room isn’t exactly spacious, but it’s neat and clean, which is better than you expected. In fact, it’s already shaping up to be a hundred times better than your dorm room in your university.

“Thank you,” you say meekly, ducking your head a little as you enter the room. You drop your backpack onto the chair and pretend to take interest in the small potted plant on top of the table.

“Well, I’ll let you get settled in,” Osamu says. “Tsumu’ll be back in a couple of hours, so feel free to make yourself at home in the meantime, yeah?”

“Yeah, I will. Thank you very much,” you say again.

“No problem,” Osamu waves you off nonchalantly before he turns around and leaves.

When you hear the door click shut, you sigh a breath of relief. You take a hesitant step towards the bed and run your fingers lightly along the duvet before you deem it clean enough and sink into the soft surface, relieved to finally rest your weary feet.

You think about what happened in the past week that ended up with you here, in the apartment belonging to someone with whom you’ve lost contact for more than ten years.

A week ago, a fire had broken out on the top floor of your five-story dormitory building at near midnight, the flames quickly engulfing half of the building before the authorities arrived. Fortunately, no one had died as many residents, including yourself, were busy studying for the midterm exams in the library and had safely avoided the disaster. You were also lucky that you lived on the lowest level, so much of your belongings were left relatively unscathed.

However, the building itself was nearly unsalvageable. Extensive repairs were needed before it'd even be inhabitable again, in addition to strict investigations and stringent inspections. The school had tried to allocate the students into other buildings, but rooms were limited with priority given to Omegas. With nowhere else to go, you had stayed over at your friend's place, squeezing into her tiny room together with her roommate for the time being while you sat for your exams.

When your parents heard of the incident, they immediately protested your continued stay on campus. You don't know what strings they pulled, but they managed to get you cheap accommodation nearby within a few days. It was only after you agreed to move out that you found out who said accommodation belonged to, but by then it was already too late.

A glance at the wall clock shows that it's almost 3 pm. You sit up, pat yourself on the cheeks and begin the arduous process of unpacking. Not that you’ve brought a lot of things with you; you have your textbooks, laptop, stationery, several changes of clothes, toiletries, and your favorite blanket. It's just that you're feeling awfully reluctant to even be here.

Despite that, you recognize that you have no other options. Finding an affordable room in the heart of Osaka on such short notice is virtually an impossible task. Your parents are paying for all your expenses so you can't exactly go against their wishes either. You also can't move back home because Tokyo is too far away, so you'll just have to suck it up until the end of the semester at least.

Besides, you spend most of your time on campus anyway. And according to your mother, Osamu is now a successful business owner and Atsumu a professional athlete, so it's not like you'll run into them often with their busy schedules, right?

"Hey Samu, I'm home!" an unfamiliar voice bellows outside, followed by the loud bang of the front door. "What's for dinner?"

You jump a little at that, quickly putting down the shirt in your hands to listen closely.

"I ain't your maid, you brat," Osamu retorts. "And stop banging the damn door, for god's sake."

"You stayed home all day and you couldn't even prepare a damn meal?" presumably Atsumu mocks.

"(L/N) moved in today, dumbass."

"Oh? Where is she?"

… Maybe you shouldn't have spoken so soon.

With a gulp, you close the wardrobe door and steel yourself. You open your door and peek through the slit, immediately making eye contact with a pair of honey-brown orbs. Flinching, you push the door fully open and step out of the room.

“Hello, Atsumu-san. It’s nice to see you again. Thank you for having me!” you say before you bow at him in greeting.

Atsumu stares back at you dispassionately, quirking an eyebrow before his mouth pulls into a smirk. “(F/N)-chan, is it? Well, I can’t say I feel the same. You haven’t changed at all in the last ten years, have you?”

You gape at him stupidly, at a loss for words. You know that despite your mothers’ close friendship, you and the twins had barely gotten along, only tolerating each other when the adults were nearby. As past neighbors, you had spent much of your childhood at the Miya household while your parents worked till late at night before the three of you moved away. Your presence was never a welcome one among the twins as they had barely tried to get to know you despite your numerous attempts at making friends with them. You always thought that their borderline apathy and hostility had stemmed from your conflicting personalities and interests and not actual hate, and while it may be true for Osamu, it seems like the same couldn’t be said for Atsumu.

Suddenly, a slipper hits the back of Atsumu’s head.

“Stop being rude, you jerk,” Osamu hisses, standing up from the couch.

“The hell?" Atsumu snaps, clutching his head as he turns around to bare his fangs at his brother. "I wasn’t being rude, you violent motherfu—”

“(L/N), please ignore him. You know how much of an asshole he is.”

“It’s okay!” you say quickly. “I don’t mind.” It’s not like you’re not used to it. You would've been surprised if Atsumu had smiled and greeted you back politely instead.

Osamu frowns. “Even so, you know you can tell me when he’s being mean, right? I’ll set him straight for you.”

“Excuse me? Can you stop talking like I ain’t here?”

“Really, it’s okay,” you reassure him. You don’t want to be another reason for them to fight, especially when Osamu was generous enough to offer his guest bedroom to an almost stranger like you. Besides, they’re doing enough of that on their own already. “Well, I’ll go back to unpacking now…”

“Yeah, sure,” Osamu shrugs. “By the way, we’re going out for dinner in an hour or so. You wanna join us?”

You glance over at Atsumu to gauge his reaction, but the blond has obviously lost interest in the conversation, rounding the couch to enter the other bedroom at the end of the hallway as if he hasn’t heard the suggestion.

At the lack of objection, you feel a sudden uncertainty. While the child in you is screaming at you to refuse the invitation, your adult self acknowledges that the Miya twins are not the same little boys who used to make fun of you behind your parents’ backs anymore. Like Atsumu said, it’s been ten years since you’ve last seen them in person. Maybe it’ll be a good idea to let go of past grievances and get to know each other all over again, especially if you’re going to be stuck with them for the foreseeable future.

With that thought in mind, you smile at Osamu tentatively. "Sure, I'd love to."


	2. Chapter 2

**Notes for the Chapter:**

> joint distributions are killing me TT  
> anyway here's chapter 2 a little earlier than expected lol

The night goes smoothly enough, to your pleasant surprise. 

The three of you talk about your respective lives and briefly update each other on what happened after you moved away before the start of middle school over some ramen, which is delicious.

Even though you've known half of the stories from your mother who often gossiped to you about ‘those handsome twins’, hearing about them first hand is still another experience entirely. You learn that Atsumu is now playing in the professional volleyball league for MSBY Black Jackals and Osamu, who had opened up Onigiri Miya just a few streets away, is planning on expanding his business soon. In turn, you tell them about your studies which pique Osamu’s interest since there’s a bit of an overlap with some of his courses from college.

It seems as if whatever lingering hostility the twins had for you has largely disappeared with enough time and distance, and you soon find yourself laughing as you listen to Atsumu’s tales and Osamu’s dry retorts to his brother’s poorly disguised bragging.

You can see why the twins are popular. Besides their conventionally good looks, they’re also witty and charming in different ways that contrast and blend nicely to create a fun and playful atmosphere. From their appearances and personalities alone, you’re also pretty sure they presented as Alphas. A pair of rather attractive Alphas, you'll say. Besides, judging by the number of double-takes and sneaky glances from the group of high school girls from two tables away, they probably think so too.

“E-Excuse me,” a voice stutters next to you, making you startle. You look up and see that it's one of the girls. She looks cute, with dark, wavy hair falling over her shoulders and framing her face delicately. You think she’s probably an Omega. “I was wondering… if I could take a picture with both of you?” she asks the twins.

The way Atsumu’s face darkens at the interruption catches your eye, but it’s gone as soon as it appears. He smiles at the girl charmingly. “Of course. I wouldn’t be able to say no to such a cute girl like you anyways.”

“Yeah, right,” Osamu mutters under his breath, which makes you giggle a little.

“Umm…” the girl then turns to look at you pleadingly, holding out her phone to you.

You stare at it in confusion for a second before you understand what she wants. “Oh, sure!”

After taking the photo, the girl thanks the three of you profusely before running back to her table, her friends chattering around her in excitement.

“You guys are still as popular as ever, huh?” you tease lightly.

“Well, what can I say? Some people are just born lucky,” Atsumu grins smugly before jabbing a thumb at Osamu. “Though I can’t say the same for this glutton over here. He’s kinda let himself go ever since— Hey! Put that back!”

“Too late,” Osamu sneers before wolfing down the stolen piece of pork belly in one bite.

“I was saving that, you asshole!” Atsumu whines plaintively, unable to enact his revenge since Osamu has long finished his own food.

“Should have thought of that before you opened your big mouth.”

“You can have some of mine,” you offer, mouth moving before you could think it through. Oh no, was that too forward of you? Warmth creeps up your face at your little slip-up, but it’s too late to take it back now.

There’s a moment of silence. You feel like you’re dying inside when you notice the look of discomfort on Atsumu’s face and the slight furrow of Osamu’s brows at your bold offer. For a second, you think you’re going to get laughed at and harshly rejected, so it comes as a surprise when none of that happens.

“Thank you for the food,” Osamu drawls before snatching up the piece of pork.

Atsumu looks on in disgust. “You see what I mean?”

Your shoulders slump in relief. The twins start bickering again, but you’re too distracted by your thoughts to pay attention. You eat your food silently, smiling and nodding along whenever one of them turns to address you.

The walk back to the apartment is a quiet one as the three of you twist and turn through the backstreets of Amagasaki. You lag behind the twins on the sidewalk as you enjoy the chilly night air that threads through your hair, your belly heavy with satisfaction. 

Illuminated by the dim streetlights, your eyes are drawn to the two figures in front of you. The sight feels familiar yet foreign at the same time— because how many times had you stared at them from behind like this as a child? Yet this time, their backs are not getting further and further away from you; Osamu and Atsumu are walking ahead of you at a comfortable distance, and you feel the slightest bit of pressure lift off your chest.

When you get back to the apartment, Atsumu stops you from going back to your room the moment you step out of the bathroom. 

“Hey, let’s have a meeting.”

"A meeting?"

"Yeah, to discuss rules and shit."

You follow Atsumu to the dining area where Osamu is already waiting for you next to a small whiteboard attached to the wall. At the top are the words 'HOUSE RULES' written in red and underlined three times.

"Please sit," Osamu says, gesturing at the lone chair in front of him.

You take a seat warily.

“So,” Atsumu begins, taking his place on the other side of the whiteboard. “We called this meeting today to discuss something important. Something very important that absolutely needs to be addressed before we can even begin our I-don’t-know-however-the-fuck-long coexistence together. You may be wondering:  _ what the hell is this about, Atsumu-san? _ ” 

He pauses expectantly.

“... What is this about, Atsumu-san?” you ask dutifully.

“Good question! Well, as you can see from this over here,” he taps the end of his marker on the board for emphasis, “We have rules in this house. Rules that absolutely have to be followed, else there will be… consequences.”

Osamu sighs. “Can you get on with it? We don’t have all day.”

“Shut up! Anyway, the first rule is—” Atsumu fumbles in his pocket for a crumpled piece of paper. He squints at it. “Umm, ‘You must always follow the cleaning schedule.’ Yeah, cleaning. Write that down, Samu.”

Osamu writes down ‘Cleaning’.

“Okay, the second rule is—”

“Wait,” Osamu interrupts. “Aren’t you gonna elaborate on that?”

“It’s not on the list,” Atsumu shrugs. “We’ll get back to that later. Anyway, the second thing on this list is ‘I expect you to respect my privacy.’ Huh. Yeah, you better do that—”

“You’re hopeless,” Osamu snaps, snatching the paper from Atsumu’s hands. “Hey, who wrote this?”

“Omi-kun, of course! He even taped it to my door and everything. Neat, right?”

“Sounds like these rules only apply to you, dumbass," Osamu quickly scans through the paper before his lips quirk in amusement. "I can't believe it. They’re all threats."

“Erm…” you raise your hand slowly. The twins turn around to look at you at the same time as if they just remembered that you're here too. “Do you not live here, Atsumu-san?”

Atsumu raises an eyebrow. "No? Why would I? I live at the dorms near the gym."

This is news to you. You know that the apartment belongs to Osamu, but you've always thought that Atsumu lives here too. You're not complaining though; living with only one Miya makes the whole situation a little less daunting.

"He's just a leech that enjoys mooching off others," Osamu says derisively.

"Oi. I know where you sleep at night, dear brother."

"Your point? As if I don't know where  _ you _ sleep, ugly brother."

At the enraged look on the blond's face, you sigh to yourself, the beginnings of a migraine forming at the back of your head. 

Do they always fight like this? Even as adults? Well, at least they're just using their mouths and not their fists this time. You suppose that some things will never change, suddenly grateful that the acidic pheromones that are surely thick in the air right now will only have a minimal effect on you.

"Regarding the first rule, how would you like to divide up the chores, Osamu-san?" you interject gently before a fight could break out.

In the end, you three are able to establish some basic rules. Your rooms are your own responsibilities, and no one can enter each other’s room without permission. You will clean the common areas like the living room and the bathroom together on the weekends. You’re allowed to use the kitchen, but only to prepare meals with your own ingredients. Laundry is to be done together every two days to conserve water. Noise must be kept to a minimum after 11 pm. And most important of all, do not hog the bathroom between 5 am and 6 am.

(“What? Why?” you ask incredulously. Not that you’re usually awake so early in the morning, but what if there’s an emergency?

“You don’t need to know why—”

“Because that’s when he takes his morning shits before work.”

“Will you  _ shut up _ , Tsumu!”)

Of course, more rules can be added if required, but you’re overall happy with what you have now. Not to say that you love rules, but having firm boundaries and clear expectations will only make everything better in the long run, especially when it comes to the Miya twins.

After that, you finally retire to your new bedroom. You lie on the bed with your blanket wrapped snugly around you while you play some songs from your favorite band as you reply to the messages from your friends and family, reassuring them that you're safe and sound. The catchy tunes manage to drown out the television noises coming from the living room, but it doesn't help much in settling the restlessness in your chest. 

Regardless, you have a good feeling about this. The twins have not been unkind to you this evening. In fact, they're even treating you like a long lost friend instead of the clingy nuisance they always claimed you were.

You just hope that this time, you’ll actually get along with them.

**Author's Note:**

> This is me stress writing when I should really be studying for my exams, lol. Updates will be sporadic depending on the amount of free time I have, but I'll try my best to keep to a schedule.
> 
> Please feel free to let me know your thoughts in the comment section below :D


End file.
